Drug Interaction Report

Tolterodine and Miconazole Topical: Interaction Details

A pharmacist-reviewed analysis of the Tolterodine and Miconazole Topical interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Tolterodine

Detrol
+

Miconazole Topical

Aloe Vesta Antifungal Critic-Aid Clear DermaFungal Dermagran Desenex® Fungoid® Tincture Lotrimin® AF Athlete's Foot Powder Lotrimin® AF Athlete's Foot Spray Deodorant Powder
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Moderate
Can be significant — usually manageable with monitoring.
How we grade severity & evidence

Severity levels

  • Contraindicated: These should generally not be used together.
  • Major: Potentially serious — often needs a change or close monitoring.
  • Moderate: Can be significant — usually manageable with monitoring.
  • Minor: Usually limited clinical impact.

Evidence grades

  • Established: Well documented — supported by controlled studies or strong clinical data.
  • Probable: Good supporting evidence, though not definitively proven.
  • Suspected: Some evidence suggests this interaction, but it is not well established.
  • Possible: Limited or conflicting evidence; the interaction may occur.
  • Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.

Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.

Of 59 documented Tolterodine interactions, 8 are rated moderate — including this one.
Onset
rapid
Evidence
probable
Severity
Moderate

What happens

Enhanced tolterodine bioavailability in individuals with deficient cytochrome P450 2D6 activity

Interaction Deep Dive

Tolterodine is metabolized via hydroxylation catalyzed by cytochrome P450 2D6 (CYP2D6) and via N-dealkylation catalyzed by cytochrome P450 3A4 (CYP3A4). The high CYP2D6 specificity of tolterodine suggests that extensive metabolizers are not likely to be affected by the coadministration of a CYP3A4 inhibitor. However, in subjects deficient in CYP2D6, the oral clearance of tolterodine decreased by 60% when ketoconazole, a potent CYP3A4 inhibitor, was coadministered1. , A dose adjustment of tolterodine is warranted in patients taking miconazole or other potent CYP3A4 inhibitors. The recommended dose of tolterodine is 1 mg twice a day 2, and the recommended dose of the long-acting formulation is 2 mg per day 3.

Why it happens (mechanism)

Inhibition of cytochrome P450 3A4-mediated tolterodine metabolism

Common questions

Can I take Tolterodine and Miconazole Topical together?

Enhanced tolterodine bioavailability in individuals with deficient cytochrome P450 2D6 activity Always confirm with your pharmacist or prescriber before making any change.

How serious is the Tolterodine and Miconazole Topical interaction?

It is rated moderate. Can be significant — usually manageable with monitoring.

How quickly could this interaction happen?

The documented onset is "rapid". Effects can appear quickly, often within about 24 hours of combining the drugs.

How strong is the evidence for this interaction?

The evidence is graded "probable". Good supporting evidence, though not definitively proven.

Questions for your pharmacist

  • Does my dose of Tolterodine or Miconazole Topical need adjusting while I take them together?
  • What symptoms should prompt me to call you or my prescriber right away?
  • Does the timing of my doses matter for this combination?
  • Is there anything you'd monitor while I'm on both?

References (3)

  1. Brynne N, Forslund C, Hallen B, et al: Ketoconazole inhibits the metabolism of tolterodine in subjects with deficient CYP2D6 activity. Br J Clin Pharmacol 1999; 48:564-572. PubMed
  2. Product Information: DETROL(R) oral tablets, tolterodine tartrate oral tablets. Pfizer, New York, NY, 2005. DailyMed
  3. Product Information: DETROL(R) LA extended release capsules, tolterodine tartrate extended release capsules. Pfizer, New York, NY, 2005.
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Tolterodine

Keep reading about Tolterodine

All Tolterodine interactions (59)
Also serious with: Ketoconazole Topical Oxaliplatin Injection Dasatinib Arsenic Trioxide
Miconazole Topical

Keep reading about Miconazole Topical

All Miconazole Topical interactions (37) Miconazole Topical drug information
Also serious with: Pimozide Deuruxolitinib Amiodarone Carvedilol
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Tolterodine + Activated Charcoal Grapefruit Henbane Scopolia St. John's Wort 1,3-dmaa Acacia Rigidula Active Hexose Correlated Compound (ahcc) + 170 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.